Older kernels don't support statistics, to avoid retries
make use of netlink policy dumps to figure out which
flags kernel actually supports.
Signed-off-by: Jakub Kicinski <k...@kernel.org>
---
netlink/msgbuff.h | 6 ++
netlink/netlink.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++
netlink/netlink.h | 2 +
3 files changed, 159 insertions(+)
diff --git a/netlink/msgbuff.h b/netlink/msgbuff.h
index 24b99c5a28d7..7d6731fc24a3 100644
--- a/netlink/msgbuff.h
+++ b/netlink/msgbuff.h
@@ -81,6 +81,12 @@ static inline bool ethnla_put_u32(struct nl_msg_buff
*msgbuff, uint16_t type,
return ethnla_put(msgbuff, type, sizeof(uint32_t), &data);
}
+static inline bool ethnla_put_u16(struct nl_msg_buff *msgbuff, uint16_t type,
+ uint16_t data)
+{
+ return ethnla_put(msgbuff, type, sizeof(uint16_t), &data);
+}
+
static inline bool ethnla_put_u8(struct nl_msg_buff *msgbuff, uint16_t type,
uint8_t data)
{
diff --git a/netlink/netlink.c b/netlink/netlink.c
index e42d57076a4b..f79da12d3eee 100644
--- a/netlink/netlink.c
+++ b/netlink/netlink.c
@@ -135,6 +135,157 @@ bool netlink_cmd_check(struct cmd_context *ctx, unsigned
int cmd,
return !(nlctx->ops_flags[cmd] & cap);
}
+struct ethtool_op_policy_query_ctx {
+ struct nl_context *nlctx;
+ unsigned int op;
+ unsigned int op_hdr_attr;
+
+ bool op_policy_found;
+ bool hdr_policy_found;
+ unsigned int op_policy_idx;
+ unsigned int hdr_policy_idx;
+ uint64_t flag_mask;
+};
+
+static int family_policy_find_op(struct ethtool_op_policy_query_ctx *ctx,
+ const struct nlattr *op_policy)
+{
+ const struct nlattr *attr;
+ unsigned int type;
+ int ret;
+
+ type = ctx->nlctx->is_dump ?
+ CTRL_ATTR_POLICY_DUMP : CTRL_ATTR_POLICY_DO;
+
+ mnl_attr_for_each_nested(attr, op_policy) {
+ const struct nlattr *tb[CTRL_ATTR_POLICY_DUMP_MAX + 1] = {};
+ DECLARE_ATTR_TB_INFO(tb);
+
+ if (mnl_attr_get_type(attr) != ctx->op)
+ continue;
+
+ ret = mnl_attr_parse_nested(attr, attr_cb, &tb_info);
+ if (ret < 0)
+ return ret;
+
+ if (!tb[type])
+ continue;
+
+ ctx->op_policy_found = true;
+ ctx->op_policy_idx = mnl_attr_get_u32(tb[type]);
+ break;
+ }
+
+ return 0;
+}
+
+static int family_policy_cb(const struct nlmsghdr *nlhdr, void *data)
+{
+ const struct nlattr *tba[NL_POLICY_TYPE_ATTR_MAX + 1] = {};
+ DECLARE_ATTR_TB_INFO(tba);
+ const struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
+ DECLARE_ATTR_TB_INFO(tb);
+ const struct nlattr *policy_attr, *attr_attr, *attr;
+ struct ethtool_op_policy_query_ctx *ctx = data;
+ unsigned int attr_idx, policy_idx;
+ int ret;
+
+ ret = mnl_attr_parse(nlhdr, GENL_HDRLEN, attr_cb, &tb_info);
+ if (ret < 0)
+ return MNL_CB_ERROR;
+
+ if (!ctx->op_policy_found) {
+ if (!tb[CTRL_ATTR_OP_POLICY]) {
+ fprintf(stderr, "Error: op policy map not present\n");
+ return MNL_CB_ERROR;
+ }
+ ret = family_policy_find_op(ctx, tb[CTRL_ATTR_OP_POLICY]);
+ return ret < 0 ? MNL_CB_ERROR : MNL_CB_OK;
+ }
+
+ if (!tb[CTRL_ATTR_POLICY])
+ return MNL_CB_OK;
+
+ policy_attr = mnl_attr_get_payload(tb[CTRL_ATTR_POLICY]);
+ policy_idx = mnl_attr_get_type(policy_attr);
+ attr_attr = mnl_attr_get_payload(policy_attr);
+ attr_idx = mnl_attr_get_type(attr_attr);
+
+ ret = mnl_attr_parse_nested(attr_attr, attr_cb, &tba_info);
+ if (ret < 0)
+ return MNL_CB_ERROR;
+
+ if (policy_idx == ctx->op_policy_idx && attr_idx == ctx->op_hdr_attr) {
+ attr = tba[NL_POLICY_TYPE_ATTR_POLICY_IDX];
+ if (!attr) {
+ fprintf(stderr, "Error: no policy index in what was
expected to be ethtool header attribute\n");
+ return MNL_CB_ERROR;
+ }
+ ctx->hdr_policy_found = true;
+ ctx->hdr_policy_idx = mnl_attr_get_u32(attr);
+ }
+
+ if (ctx->hdr_policy_found && ctx->hdr_policy_idx == policy_idx &&
+ attr_idx == ETHTOOL_A_HEADER_FLAGS) {
+ attr = tba[NL_POLICY_TYPE_ATTR_MASK];
+ if (!attr) {
+ fprintf(stderr, "Error: validation mask not reported
for ethtool header flags\n");
+ return MNL_CB_ERROR;
+ }
+
+ ctx->flag_mask = mnl_attr_get_u64(attr);
+ }
+
+ return MNL_CB_OK;
+}
+
+static int get_flags_policy(struct nl_context *nlctx, struct nl_socket *nlsk,
+ unsigned int nlcmd, unsigned int hdrattr)
+{
+ struct nl_msg_buff *msgbuff = &nlsk->msgbuff;
+ struct ethtool_op_policy_query_ctx ctx;
+ int ret;
+
+ memset(&ctx, 0, sizeof(ctx));
+ ctx.nlctx = nlctx;
+ ctx.op = nlcmd;
+ ctx.op_hdr_attr = hdrattr;
+
+ ret = __msg_init(msgbuff, GENL_ID_CTRL, CTRL_CMD_GETPOLICY,
+ NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP, 1);
+ if (ret < 0)
+ return ret;
+ ret = -EMSGSIZE;
+ if (ethnla_put_u16(msgbuff, CTRL_ATTR_FAMILY_ID, nlctx->ethnl_fam))
+ return ret;
+ if (ethnla_put_u32(msgbuff, CTRL_ATTR_OP, nlcmd))
+ return ret;
+
+ nlsock_sendmsg(nlsk, NULL);
+ nlsock_process_reply(nlsk, family_policy_cb, &ctx);
+
+ ret = ctx.flag_mask;
+ return ret;
+}
+
+u32 get_stats_flag(struct nl_context *nlctx, unsigned int nlcmd,
+ unsigned int hdrattr)
+{
+ int ret;
+
+ if (!nlctx->ctx->show_stats)
+ return 0;
+ if (nlcmd > ETHTOOL_MSG_USER_MAX ||
+ !(nlctx->ops_flags[nlcmd] & GENL_CMD_CAP_HASPOL))
+ return 0;
+
+ ret = get_flags_policy(nlctx, nlctx->ethnl_socket, nlcmd, hdrattr);
+ if (ret < 0)
+ return 0;
+
+ return ret & ETHTOOL_FLAG_STATS;
+}
+
/* initialization */
static int genl_read_ops(struct nl_context *nlctx,
diff --git a/netlink/netlink.h b/netlink/netlink.h
index 1012e8e32cd8..799f2556cb31 100644
--- a/netlink/netlink.h
+++ b/netlink/netlink.h
@@ -66,6 +66,8 @@ bool netlink_cmd_check(struct cmd_context *ctx, unsigned int
cmd,
bool allow_wildcard);
const char *get_dev_name(const struct nlattr *nest);
int get_dev_info(const struct nlattr *nest, int *ifindex, char *ifname);
+u32 get_stats_flag(struct nl_context *nlctx, unsigned int nlcmd,
+ unsigned int hdrattr);
int linkmodes_reply_cb(const struct nlmsghdr *nlhdr, void *data);
int linkinfo_reply_cb(const struct nlmsghdr *nlhdr, void *data);
--
2.26.2
